Diego Costa has been the talisman of Guus Hiddink's second interim spell as Chelsea manager. Having scored just four goals in 20 appearances as confidence crumbled and "palpable discord" reigned under Jose Mourinho, the Spain international has registered 10 goals and six assists in 14 matches in all competitions since Hiddink's arrival in December.

With Chelsea needing to balance their late surge for a place in the Premier League's top four with their Champions League campaign -- they're 2-1 down ahead of next week's round of 16 second leg against Paris Saint-Germain -- Hiddink may need to rotate his squad.

"There is a possibility, yes," Hiddink said last week when asked if he was considering resting Costa for the visit of Stoke but at his prematch news conference on Friday, he appeared to backtrack when he said: "He wants to play every game but I must be careful with that. Tomorrow he will start. Who am I to stop this man?"

In any case, Chelsea may rest Costa in the coming weeks and if he is on the bench, here's a list of contenders who could replace him...

1. Bertrand Traore

His name meant very little to most Chelsea supporters as recently as two months ago, but Traore has been another big success story under Hiddink. Kept from going on loan last summer with a view to featuring in the first team, the 20-year-old made just three substitute appearances under Jose Mourinho.

Hiddink ran the rule over several of Chelsea's fringe youngsters in January and concluded that Traore had more to offer. Injuries to Loic Remy and Radamel Falcao -- combined with the "preseason" shape of Alexandre Pato on arrival from Corinthians in January -- helped Traore's cause and encouraged his manager to try him as a central striker.

"If I see Traore now compared to when I came in, he was always ambitious," Hiddink said earlier this week.

"He's a very fresh guy and I like his attitude. He's not afraid to make errors and he's not influenced by external circumstances."

Traore has seized his opportunity with both hands. Three goals in three substitute appearances and an assist for Costa on his first Premier League start against Norwich means the 20-year-old is now firmly established as Hiddink's attacking Plan B.

2. Loic Remy

Just 32 minutes of first-team action in more than two months has left Remy at a crossroads in his career. Persistent calf injuries have plagued the Frenchman ever since Hiddink's arrival, allowing Traore to leapfrog him in the pecking order and necessitating the loan signing of Pato in January.

Costa's return to form has also come at a bad time for Remy. "His attitude in training is very good," Hiddink said of the former Newcastle striker earlier this week.

"He's working hard but if young guys are knocking on the door there is competition."

Disillusioned at his lack of first-team opportunities at Chelsea, Remy was the subject of interest from Leicester City, Newcastle and the Chinese Super League in January. If he remains behind Costa and Traore in the pecking order, the signs are that he will look elsewhere again at the end of the season.

Alexandre Pato has yet to feature for Chelsea since signing on loan in January.

3. Alexandre Pato

Fit enough to make his first appearance on the bench against Norwich City in midweek.

But while Pato might be ready, he is running out of time. Chelsea have 10 Premier League matches remaining and could, in the worst-case scenario, exit the Champions League and FA Cup next week. His inability to slot immediately into Hiddink's plans has also allowed Traore to fill the void and gain the trust of the manager.

A low-cost, low-risk loan signing, Chelsea have little to lose with Pato. The Brazilian, in contrast, is desperate to prove he can still shine in European football, but he faces a fight just to get into Hiddink's team ahead of more settled and proven rivals like Traore and Remy.

4. Radamel Falcao

Four months have passed since the Colombian last kicked a ball competitively for Chelsea and it is highly unlikely he will do so again before his loan agreement expires this summer.

Falcao is training at Cobham and doing individual work as part of the rehabilitation programme put in place by Chelsea's medical staff. Hiddink still refuses to put any kind of timeframe on the striker's recovery from a "very serious" thigh injury sustained around the turn of the year, and it's easy to see why.

At this stage the stakes for Falcao are much higher than simply working his way back into Hiddink's plans. The Colombian has never been fit for a meaningful period of time since rupturing his ACL for Monaco prior to the 2014 World Cup. If he cannot convince potential suitors that his body can withstand the rigours of top-level football, his career is at risk.

The arrival of Pato highlighted a presumption from those in the corridors of power at Stamford Bridge that Falcao will not play for Chelsea again.